X-ray apparatus



April 23, 1929. A. MUTSCHELLER X-RAY APPARATUS Filed April 30, 1927 3 Sheets-Sheet 1 INVENTOR Hula mi e! JEUREl 1 M zak QMM ATTORNEY April 23, 1929.

MUTSCHELLER X-RAY APPARATUS I 3 Sheets-Sheet 3 Filed April 30. 1927 IEURES sun: 5

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Patented Apr. 23,1929.

UNITED STATES PATENT OFFICE.

ARTHUR MUTSCHELLEB, OF NEW YORK, N. Y., ASSIGNOR, To WAPPLER ELECTRIC CO. INC., A CORPORATION OF NEW YORK.

X-RA'Y APPARATUS.

Application filed April 30, 1927. Serial No. 187,793.

My invention relates to X-ray apparatus, and more particularly to a manner of housing and arranging the various electrical and mechanical components of an X-ray system wherein all the various parts are incorpo-' rated separate and distinct units, one or more .of which may be used at a time.

Among the advantages attained by my in vention are the following: 1 '10 First, greater compactness of the entire apparatus.

Second, less danger from high voltages, combined with greater electrical efiicieney, due to the use of shorter leads. L

Third, better insulation, due to the complete immersion, in oil, of certain parts carrying high voltages, as against other parts carrying lower voltages.

Fourth, more thorough cooling, due to the immersion in oil. of parts not heretofore so immersed, and which would otherwise become heated.

Fifth, certain constructional advantages, which reduce materially the cost of production.

' Sixth, various other advantages, hereinafter set forth more particularlyat length. My invention is concerned chiefly with X-ray machines of the valve tube rectifier type, such as those described in my pending applications, Serial No. 101,102 filed April 10, 1926, and Serial No. 136,4Q0, filed September 20, 1926. In the machines described in each of my said applications a complete and '35 selfcontained X-ray unit, energized by currents supplied to it from an extrinsic source, furnishes rectified currents of high potential, suitable for energizing the 7 main discharge circuit of an X-ray tube, and also furnishes 40 low tensioncurrents for heating the cathode filament of the X-ray tube, as well as the cathode filament of any valve tubes employed. Inthe prior art there have been used X-ray apparatus comprising a high'tension transformer, separately supported valve tubes and an X-ray tube, so combined as to develop high tension discharges of unitary direction through the X-ray tube. However, in the machines just mentioned, due to the neeesslty for using long leads between component parts, and to the requirement for individual supports for each part, there are severe limiers and transformer being immersed in oil andhoused within a casing of box-like form,

this casing being provided with a cover, and

the various valve tubes and certain other parts being mounted thereupon.

The cover just mentioned is also adapted for use with a change-over switch, also housed within the casing and so arranged that by operating the switch, the machine can be instantly set for series or parallel connections between certain parts, thus changing the-operating conditions of the machine, all as described in my pending application for an X-ray machine, filed September 20, 1926, Serial No. 136,420. a

I have found it to be practicable and very advantageous to mount certain transformers bodily within and upon the high tension insulators usedin my mechanism, and to arrange these transformers, thus mounted, so that their principal component parts are wholly or partially immersed in the oil contained in the casing. The transformers thus contemplated are used for generating currents employed in heating the cathode filaments of the Xmay tube and various valve tubes, these valve tubes bein mounted bodily upon the aforesaid cover 0 the casing, and connected with the transformers last mentioned, by very short leads.

.Reference is made to the accompanying drawings forming a part .of-this specification, and in which like reference characters indicate like parts throughout the several figures.

Figure 1 is a view-showing the oil tank serving as a housing and the mechanism contained therein, and is a section on the line 1-1 of Figure 2, looking in the direction in di'eated by the arrows.

Figure 2 is a section on theline 22 of 100 Figure 1, looking in the direction indicated by thearrows. f

Figure 3 is a section on the line 33 of Figure 1, looking in the direction indicated by the arrows.

Figure 4 is a plan view of the mechanism shown in Figure 3.

Figure 5 is a vertical section through one of the high tension insulators, and shows the transformer carried thereby.

Figure 6 is a diagram of the wiring.

A tank 7 serves the double purpose of an oil tank and acasing for containing most of the mechanism. This tank is provided with a cover 8, in the form of a flat plate, detachably fitted upon the tank and serving as a support for a portion of the mechanism.

Located within the bottom of the tank and spaced widely apart are a pair of pillow sills 9, 9, and extending upwardly from them are lifting posts 10. Each lifting post is provided with' a neck portion 11 extending through a hole in the pillow sill, and secured by a nut 12, as indicated by dotted lines in Figure 2. The lifting posts each extend from bottom to top of the tank, and are each pro-' vided with an eye 13. There are four of these eyes, and they are useful in lifting out of the tank the mechanism therein contained, whenever this is desirable.

Disposed adjacent the pillow sills 9, 9, and parallel thereto, are foot sills 9 of which there are two. Extending crosswise of the pillow sills 9, 9 and foot sills 9, 9 are a pair of tie beams 15, 15, shown more particularly in Figure 3. These tie beams are secured to the pillow sills 9, 9by means of bolts 16, as may be understood from Figures 1 and 2.

A transformer core is shown at 17, and rests upon the pillow sills 9, 9, as indicated in Figure 3. Disposed upon opposite sides of the transformer core are a pair of clamping blocks 18, 18, each provided with a relatively thick portion 19,-as indicated more particularly in Figure 2.

Bolts 20 of the form shown in Figure 3 each extend through one of the clamping blocks 18, 18, and also through a spacing block 18, one of the tie beams 15, and one of the foot sills 9 I Mounted upon the transformer core 17, which is in this instance inclosed, are two distinct primary windings 21, 22, and encircling ing upon the foot sills 14 are a number of condenser plates 27, 28, so grouped as to con stitute two distinct condensers, located adj acent opposite ends of the foot sills 9, 9.

Located within the upper portion of the tank is a condenser block 30 of the form shown in Figure 3. It extends entirely across the tank, and is provided with a pair of downwardly extending portions 31, 31, formed to engage the upper edges of the condenser plates. For this purpose the downwardly extending portions 31, 31 are provided with slots 32, into which the upper edges of the condenser plates extend. Thus the condenser plates are firmly fixed in position, being held at both top and bottom.

Conductively connected with the condensers and extending upwardly therefrom are a number of metallic strips 33, 33, arranged in two sets as shown, and at the top connected with the condenser terminals appearing at 34, 35. Similarly, a number of condenser strips 36, 36, lead to the condenser terminals 37. 38, as shown in Figure 1. 1

Thus one condenser, made up of the plates 27, has'its terminals 37 and 38, and the other condenser, made up of the plates 28, has its terminals 34 and 35.

A switch base 39, having the form of a plate, is mounted upon the clamping blocks 19, and by means of screws 40 is secured directly to the relatively thick portion 19 there- Jgirried by the switch base 39 and extend ing upwardly therefrom is a rocking shaft 41 made of metal, a stationary post 42 also of metal, and an actuating shaft 43. This actuating shaft is made of metal, and extends through a hole in the cover 8, which serves as a bearing. The'actuating shaft 43 is adapted to be rocked. The switch base 39 also carries a metallic post 44 which is stationary and which extends upwardly from it like the post 42.

The two shafts 41 and 43 and the two posts 42 and 44 are provided with tubular insulating members 45.

Mounted rigidly upon the actuating shaft 43 is a crank 46, and a similar crank 47 is mounted upon the upper end of the rocking shaft 41. A pitman 48 extends from the crank 46 to the crank 47, in order to enable these two cranks to be actuated in unison, by rocking movements of the actuating shaft 43.

A contact arm 49 is mounted rigidly upon the rocking shaft 41, and another contact arm 50 is mounted rigidly upon the actuating shaft 43. A metallic post 61 is located midway between the rocking shaft 41 and the actuating shaft 43.

The parts just described are so formed and arranged that when the actuating shaft 43 is turned in a clockwise direction according to Figure 1 the two contact arms 49 and 50 are brought into engagement with the metallic post 61 and thus into metallic communication with each other, and when the actuating shaft 43 is turned in a counterclockwise direction according to this figure, the contact arms 49 and 50 are disengaged from each other, the contact arm 49 being.

contact button 52, carried by the post 44 and constituting practically an enlarged portion thereof.

Mounted rigidly upon the upper end of the actuating shaft 43 is.a rocking arm 53, of the form shown more particularly in Figure 4. Associated with the rocking arm 53 is an indicator 54, shown more particularly in Figure 4, and provided with legends High and Low, these legends referring respectively to the voltage to be controlled by aid of the actuating shaft 43, or rather by the switch of which this shaft is a part.

A cord 55 is connectedwith one end of the rocking arm 53, and connected with the opposite end of this rocking arm is another cord 56. The cords 55 and 56 are threaded through eyes 57, and are pulled by hand as occasion requires, in order to shift the rocking arm 53 back and forth, thus operating the switch.

Mounted upon the cover 8 are a pair of binding posts 58, 59, through which current is supplied to the primary circuit of the transformer, and a binding post 60 which is used as a ground connection.

Mounted upon the cover 8 and extending upwardly therefrom are four high tension insulators 62, 63, 64 and 65, which are of tubular form, and are made of insulating material, such as bakelite, electrose, mica, porcelain or glass, They are respectively provided with neck portions 62, 63 64? and 65 integral with them and also of tubular form, as may be understood from Figure 1, and which extend downwardly through holes in the cover.

These neck portions are encircled by cylindrical sleeves 66, 67, 68 and 69 of insulating material, such as formica, hard rubber composition, electrose or the like, and are accurately formed and fitted.

Each sleeve 66, 67, 68 and 69 is by measurement a little shorter than the neck portion upon which it is mounted, but is of such length as to extend a little below the bottom thereof when theparts are in position and supported by the cover 8, asmay be under= stood from Figure 5. Each sleeve is held in place by a closure plate 70, having the form of a disk and pressing tightly against its lower end, these parts being thus rendered oil-tight. i j

Encircling the sleeve 68 and thus carried by the insulator 64 is a winding 72, serving as the primary winding of a little step-down transformer for generating small currents of low potential used for heating the cathode filament of an X-ray tube, as hereinafter de scribed. Similarly, two other primary windings 71 and 73 of the same kind encircle the sleeves 67 and 69, carried by the insulators 63 and 65. f

The insulator 62 does not contain any transformer mechanism, but the insulators 63, 64 and 65, carrying the respective primary windings 71, 7 2 and 73, as above described, contain certain parts coacting with the primary windings, and together therewith constituting three small transformers, onefor each of the three insulators.

As the parts carried by the insulators 63, 64 and 65 are alike for each of the three insulators, I will describe these parts with reference to the insulator 65 alone, as shown more particularly in Figure 5.

The insulator 65 is provided internally with an annular shoulder 65*, and resting upon this shoulder is an anchor disk 65", made of metal and provided with a socket 65 integral therewith and extending upwardly therefrom.

A metal bolt 65 extends downwardly through a hole in the disk, and is fitted in place by means of a bushing 65 Below the anchor disk 65 is a laminated core 65 o fsoft iron, fitted into a tube 65 of insulating material, such as formica, bakelite, electrose or the like, and encircling this tube is a winding 65 comprising a few turns of coarse wire, This winding is a secondary winding n- 'tffii'ng the primary winding 73 above described; these windings and the parts immediately associated therewith constituting a step-down transformer.

A supporting strip 65, made of metal, preferably iron or steel, extends centrally through the core 65, and for most practical purposes may be considered as a part thereof.

The-supporting strip is at its upperend secured to the bolt 65, its lower end being fastoned to a screw 65K This screw extends through a hole in the closure plate 70, and is engaged by a nut 65 and washer 65. By tightening the nut 65 the supporting strip 65 is placed under tensile strain, and the parts carried by it are thus held firmly in position. In order to remove the core and secondary winding, the nut 65" is loosened, and with the washer 65 removed.

The anchor disk 65 can then be lifted out, carrying with it the core and secondary winding, and this group of parts may now be handled practically as a single unit.

The removal of the nut 65* disengages the closure disk 70,. and thereby releases the sleeve 69 and primary winding 73.

. The oil level of the oil tank 7 is indicated in Figure 3 by a line, and the legend Oil level.

With the high tension insulators mounted in position uponthe casing and the casing filled to the level indicated with the oil, the three primary windings 71, 72 and 73 are completely immersed.- in oil, and thereby thoroughly insulated. Even the laminated cores and primary windings have additional insulation because of the body of oil encircling them at their lower ends. Not only that, but it is merely a matter of engineering to build the cores and secondar windings of such size, and so locate them, t lat they will be wholly below the level of the oil in the tank, and by so doing to still further improve their insulation.

\Vhcncver the cover 8 is removed or replaced, it carries with it the three step-down transformers, justdescribed, so that the cover with its high tension insulators and the low tension transformers may in practice he handled as a single unit.

The low tension transformers are connected with the cathode filaments, as indicated in Figure 0.

A pair of valve tubes are shown "at 74, 75, and are used as rectitiers for the high tension currents.

The valve tube is mounted upon the in sulator 62 and extends upwardly therefrom, with its cathode end upward. A metallic sphere 76 is connected with the upper end of this valve tube, and is provided with a high tension tap 77, rounded to prevent corona. This tap serves practically as a high tension binding post. A clip, not shown, is detachably gripped upon it at any time, in order to connect it up with inside mechanism of any kind to which high tension currents are to be supplied.

A metallic tube 78 is connected with the sphere 76, and serves partially as a support therefor. This metallic tube is at its lower end fitted into the socket 65 located within the upper end of the high tension insulator 65, above described and shown in Figure 5, and extends therefrom obliquely upward to the left according to Figure 3.

In a similar manner the valve tube 74 is supported upon the insulator 64, the cathode end of the tube extending upward. Above the valve tube 74 is a metallic sphere 79, carrying two taps 80 and 81, like the tap 77. The sphere 79 is connected with a metallic tube 82, the latter being mounted upon theinsulator 63 and extending therefrom obliquely upward to the right acording to Figure 3.

The various parts above described are connected up as indicated in the diagram shown in Figure 6. The mechanism can be used in two ways, according to the condition of the switch mechanism, as indicated by full and broken lines in Figure 6.

An X-ray tube is shown at 83, its anode and cathtzde ends being indicated by plus and minus signs. The X-ray tube is not housed within or supported by the casing, and may be located at any point outside thereof, as may be convenient for the purpose.

The various electrical connections are shown diagrammatically in Figure 6.

From the cathode end of; the X-ray tube 83 a conductor 84 leads toa junction 85; and a shorter conductor 84 which includes a secondary winding 65 of the kind shown in Figure 5 and above described, is tapped on to the conductor 84. From the junction 85 a conductor 86 leads to the condenser 27, another conductor 87 leads to the stationary contact post 42, and another one 88 to the secondary winding 24.

From the anode end of the X-ray tube 82 a conductor 88 leads to a junction 89, and from thence three conductors 90, 91 and 92 lead respectively to the condenser 28, the stationary contact post 52 and the secondary winding 25.

Connected with the secondary winding 25 are a pair of conductors 93, 93, leading to the cathode end of the valve tube 74, the conductor 93 including a secondary winding 65 of the kind shown in Figure 5, this secondary winding mating the primary winding 72 above described. From the anode end of this tube 74 a conductor 94 leads to a junction 95, and thence two conductors 96 and 97 lead respectively to the condenser 27 and the rocking post 41.

A conductor 98 leads from the actuating shaft 43 to a junction 99, and thence a con ductor 100 leads to the condenser 28, and a pair of conductors 101, 101 lead to the cathode end of the valve tube 75, the conductor 101 including a secondary winding 65 above described, this secondary winding mating the adjacent primary winding 73. The anode end of the valve tube 75 is connected by a conductor 102 with the main secondary winding 24.

Two conductors 103 and 104 are connected with the respective binding posts and 59. The conductor 103 is also connected with two conductors 105 and 106, the comluctor 105 including the main primary winding 22, the conductor 106 similarly including the main primary winding 21.

Thus the two main primary windings 21 and 22 are in parallel with each other with respect to the binding posts 58 and 59, through which they are energized, from any suitable source of alternating current.

The primary windings 71, 72 and 78, in parallel with each other, are bridged across the conductors103 and 104 in any suitable manner, as for instance, by the conductors shown at 107', 108, 109, 110, 111, 112. 113, 114, and 116, arranged as indicated in the diagram, Figure 6.

' The main primary circuit may be traced as follows: source of alternating current (not shown), binding post 58, conductor 103 whence the circuit divides, one branch being through conductor 105 and thus through the primary winding 22, the other branch being through. the conductor 106 and thus through the primary winding 21, the two branches merging together in conductor 104, thence to binding post 59 to source of supply. This to time by the operator, by aid of the two.

cords 55 and 56, and as indicated by the diagram shown in .Figure6.

If the operator wants the machine to generate uniform currents ofrelatively hi h voltage, he pulls the cord 55, and there y brings the electric switch into the condition shown in Figures 1 and 2 and indicated by full lines in the diagram shown in Figure 6.

tube 83 may now be traced as follows:

X-ray-tube 83, conductor 88, junction 89,

conductor 92, main secondary windings and 25*,conductors 93 and 93, valve tube 74,

25 conductor 94, junction 95, conductor 97, rocking shaft 41, contact arms 49 and 50 (now in contact) actuating shaft 43, conductor 98, junction 99,conductors 101 and 101, valve tube 75, conductor 102, secondary windings 24 and 24, conductor 88 junction 85 and conductor 84 back to X ray tube 83.

The circuit just traced remains unaltered so as the switch mechanism remains undislon tur ed, and the discharge through the X-ray tube is always in the same direction. The

continuity of the discharge is due to action of the condensers. a

It will be noted that the two condensers 27 and 28, while not included in the circuit just 0 traced, are nevertheless each bridged across a as continuous, which is an object of great value for therapeutic purposes.

It may also be noted that in the circuit just traced each secondary winding produces one half of the terminal voltage and eachvalve 50, tube rectitfies one half of the total current. It

will also be observed that while the electric stresses due to the high voltage are very great, they are as far as practicable distributed uniformly throughout the system.

When the operator wants to producepulsating-relatively heavy currents of lower volt-.

age and to cut out the condensers, he simply pulls the cord 56. This places the machine in the condition indicated by broken lines in the diagfam in Figure 6. T

55 ductor 88, junction 89, conductor 92, main The secondary circuit through the X-ray.

secondary windings 25 and 25, conductors 93, 93, valve tube 74, conductor 94, junction 95, conductor 97, rocking shaft 41, contact arm 49 (broken lines), contact button 51 of stationary post 42, conductor 87, junction 85 and conductor 84, 8.4, hack to X-ray tube 83. Second, X-ray tube 83, conductor 88, junction 89,

conductor 91, contact button 52 of stationary post 44, contact arm 50 (broken lines), actuatingshaft 43, conductor 98, junction 99, con- (lllctors 101 and 101*, valve tube 75, conductor 102, main secondary windings 24 and 24*, conductor 88, junction 85,,and conductorsv84 I and 84, back to X-ray tube 83.

It may be noted that with the machine in the condition indicated by broken lines in Figure 6, the X-ray tubeis energized, first by a current generated in the main secondary windings 25 and 25 and passing freely through the valve tube 74, and then by a current generated in the main secondary windings 24 and 24 andfpassing freely throu h the valve tube 75. If now the primaries of t e two high tension transformers are connected as shown in Figure 6, then current will flow through one valve tube during one-half cycle and through the other valve tube "for the following one-half cycle; if however the polarity of one of the primaries of the igh tension transformers is reversed, then both valve tubes will pass one of the two impulses at the same time, but the voltage and the load upon the valve tubes will thereby not be noticeably af fected. The X-ray tube, however, in the former case receives during one cycle two small impulses, and in the latter one impulse broken lines in Figures 6, all time lag due to capacity is done away with, and then short time exposures can be readily made.

I do not limit myself to the precise mechanism shown, as variations may be made therein without departing from my invention, the

scope of which is commensurate with my claims.

I claim:

1'. A housing mechanism for X-ray' systems, comprising an oil tank serving as a transformer casing, a high tension transformer located within said oil tank, a cover mounted u on the top of said oil tank and normally 0 osing the same, a high tension m sulator carried by said cover and extending downwardly therethrough to a point below the upper level for oil therein, a conductor connected with said transformer and extending through said insulatbr, and a valve tube mounted upon said high tension insulator and supported thereby, said valve tube having a pair of electrodes, one of which is connected with said conductor.

2. A housing mechanism for X-ray systems, comprising an oil tank serving as a transformer casing, a high tension transformer located within said oil tank, a flat cover mounted upon the top of said oil tank and normally closing the tank, a high tension insulator carried by said cover and extending upwardly therefrom, a valve tube supported by said insulator and extending vertically upward from the same, said valve tube being provided with an anode and a cathode, said cathode being connected with said high tension transformer, and low tension transformer mechanism carried by said insulator and connected with said cathode, for supplying to said cathode currents for heating the same.

3. A housing mechanism for X-r ay systems, comprising an oil tank serving as a transformer casing, a high tension transformer located within said oil tank. a cover mounted upon said oil tank and normally closing the same, a high tension insulator mounted upon said cover and extending therethrough, a conductor extending through said insulator and connected with said high tension transformer, a valve tube mounted upon said insulator and provided with an anode and a cathode, said cathode being connected with said conductor, and a low tension transformer connected with said conductor for the purpose of supplying heating currents to said cathode, said low tension transformer being carried bodilyby said insulator.

f. A housing mechanism for X-ray systems, comprising an oil tank serving as a transformer casing, a high tension transformer mounted within said oil tank, a cover carried by said oil tank and closing the same, a high tension insulator supported by said cover and extending therethrough into said tank, a low tension transformer carried by said insulator and housed therein, a valve tube connected with said insulator and pro-- vided with an anode and a cathode, and conductors connected with said cathode, from the secondary of said low tension transformer.

5. The combination of an oil tank, a cover mounted upon said oil tank and normally closing the same, an insulator carried by said cover and extending therethrough into said oil tank, a valve tube connected with said insulator and provided with an anode and a cathode, a low tension transformer carried by said insulator and housed within said tank whenever said tank is closed by said cover, and conductors connected with said low tension transformer and extending to said cathode, for supplying heating current to said cathode.

6. A housing-mechanism for X-ray systems comprising an oil tank serving as a transformer casing, a high tension transformer housed within said oil tank, a cover mounted upon said oil tank, a high tension insulator carried by said cover and extending therethrough to a point below the upper level for a body of oil therein. low tension transformer mechanism carried by said insulator-and extendingdownwardly into said tank and thus insulated by said body of oil therein, a valve tube connected with said insulator and extending therefrom, said valve tube being provided with an anode and a cathode, and conductors connected with said cathode and with said low tension transformer, for enabling said low tension transformer to supply heating current to said cathode, said conductors being also in electrical communication with said high tension transformer.

7. A housing mechanism for X-ray systems, comprising an oil tank serving as a casing, a high tension transformer mounted within said casing, a high tension condenser mounted within said casing and'connected with said high tension transformer, a cover mounted upon said oil tank, an insulator carried by said cover and extending upwardly therefrom, a valve tube connected with said insulator and extendingtherefrom, said valve tube being provided with an anode and a cathode, connections from said cathode and said anode to said high tension transformer and said high tension condenser, the connection from said cathode extending through said insulator, and a low tension transformer carried bodily by said insulator and in electrical communication with said connections from said cathode to said high tension transformer.

8. The combination of an oil tank, a high tension transformer and a high tension condenser located within said oil tank so as to be insulated and cooled by a body of oil therein, a cover closing said tank, a valve tube located above said cover and provided with an anode and a cathode, connections from said anode to said high tension transformer and said condenser, a low tension transformer supported by said cover for the purpose of supplying heating currents to said cathode, and electrical connections from cathode to said high tension transformer and said condenser.

9. An X-ray apparatus, comprising an oil tank and a transformer contained Within said oil tank and located below the oil level-thereof, a flat cover to close said tank, and a high tension insulator extending throu h said cover and terminating in said tank be ow said oil level, a valve tube carried by said insulator and located outside of said tank, and connections between the high tension transformer and the valve tube.

10. A housing mechanism for X-ray systems, comprising an oil tank serving as a transformer casing, a high tension transformer located within said oil tank, a fiat cover mounted upon the top of said tank and normally closing the same, a high tension insulator carried by said cover and extending upwardly therefrom, and a valve tube supported by. said high tension insulator and extending vertically upward from the same, said valve tube being provided with a cathode, said cathode being connected with said high tension transformer.

11. A housing mechanism for X-ray sys tems, comprising an oil tank'serving as a transformer casing, 'a high tension trans former located within said oil tank, a cover mounted upon said oil tank and normally closing the same, a-high tension insulator carriedby said cover and extending therethrough into said oil tank, a conductor extending through said high tension insulator and con nected with, said high tension transformer, a

valve tube mounted upon said high tension insulator and provided wlth an anode, and a cathode, said cathode being connected with said conductor and a low tension transformer disposed adjacent said cover and connected with said conductor, for the purpose of supplying heating currents to said cathode.

12. A housing mechanism for X-ray systems, comprising an oil tank serving as a transformer casing, a high tension transformer housed within said oil tank, a cover sulator carried upwardly therefrom, and a valve tube s1'1ptems, comprisin transformer casing, a hlgh tens1on.trans mounted upon said oil tank, a high tension insulator carried by said cover and extending through said cover to a point below the upper level for a body of oil therein, a valve tube carried by said high tension insulator and extending therefrom,'said valve tube being provided with an'anode and a cathode, and a conductor connected with said cathode and extending therefrom to said high tension transformer.

'13." A housing mechanism for X-ray systems,. comprising an oil tank serving as a transformer casing, a .hlgh tenslon transformer located within said 011 tank, a fiat cover mounted upon ,the top of said tankand normally closing) the same, a high tension in- I y said cover and extending ported by said high tension insulator and exformer to said anode.

14. Ahousing mechanism forjX-ray sysan oil tank serving as a former housed within said oil tank, a cover mounted upon said oil tankfa high tension insulator carried by said cover and extending throu h said cover to a point below the upper level for a body of oil therein, a valve t'ube carried by said high tension insulator and extending therefrom, and connections from said valve tube to said highttension transformer for enabling said transformer to energize said valve tube.

Signed at New York city, in the county of New York and State of New York, this 23 day of April, 1927.

ARTHUR MUTSOHELLER. 

